Work with one pine cone at a time. Holding it in one hand, spread peanut butter over the pine cone, doing your best to work it into the empty seed pockets. When your pine cone is well covered, set the cone in the bowl and pour bird seed over it. The bird seed will stick to the cone. Wrap a piece of yarn or string around the top of the cone and tie it. Use the other end of the string to tie your pine cone up high in a tree where birds can find it.